1. Field of the Invention
The present invention relates to an image processing device, an image processing method thereof, and a computer readable medium which stores a program for the method. More specifically, it relates to image processing for generating an electronic file that stores a document image thereon in a reusable manner by compressing and encoding an image.
2. Description of the Related Art
In recent years, processing for reading a paper document and storing it on a computer as a compressed encoded electronic file, and processing for editing scanned data on a computer to reuse it are commonly carried out.
Since data a size of an image (especially, a color image) is large, it is necessary to store the image by reducing the data size thereof using a compression technology. However, if the image is subjected to compression at an extremely high compression ratio, an image quality will deteriorate remarkably, occurring a problem in that a character portion which is important for many documents can not be read.
As technologies for solving this problem, technologies in which a method for compression is changed depending on characteristics of an image (Japanese Patent Laid-Open Nos. H10-51642(1998) and H10-215379(1998)), a technology in which a layer structure of an image is extracted, and each layer is subjected to effective compression processing (Japanese Patent Laid-open No. 2000-306103), and a technology in which, when a plurality of images is inputted, common background images are output collectively (Japanese Patent Laid-Open No. 2007-158510), are known.
According to the above-mentioned prior art technologies it is possible to reduce data size of one or a plurality sheets of image data while keeping their image quality to some extent. However, since data included in an electronic file generated by the prior art technologies is generated from an input image, there are problems in that noises may be added to the data by scanning, thereby, the image quality of the data is degraded, or the size of the data is enlarged.
On the other hand, in order to improve appearance, many presentation documents for use of a meeting at a company are generated by being applied with style information (template) registered into presentation document generation software (e.g. Microsoft Office PowerPoint 2007) in advance. The style information generally holds information, such as positional information on a background image and a drawing object, information on a size and a color, coordinate information on header/footer areas, and information on a style of a standard figure. There are advantages in that the background image of registered style information has a good image quality, and the data size of the background image is also significantly smaller than that generated from an input image.
The applicant of the present invention devised it by attaching attention to the fact that many presentation documents are generated by being applied with style information prepared into software in advance. An object of the present invention is to achieve a high image quality and a high compression ratio using style information registered in advance for the output to a preservation format when a processing target image uses the registered style information.